Unilateral versus bilateral drainage using self-expandable metallic stent for unresectable hilar biliary obstruction.

Background: There is no consensus on the choice of either unilateral or bilateral drainage in stent placement for patients with unresectable hilar biliary obstruction. The aim of the present study was to clarify which drainage method is superior.

Methods: We retrospectively reviewed 82 patients with hilar biliary obstruction who underwent metallic stenting. These patients were divided into a unilateral drainage group (Uni group) and a bilateral drainage group (Bi group).

Results: There was no significant difference between the groups in median survival time, median stent patency period, and median complication-free survival time. The most frequent complication was stent obstruction, followed by cholangitis. Liver abscess was found at a higher frequency in the Bi group (17.6%) than in the Uni group (1.5%) (P=0.0266). There was no significant difference between the groups in the occurrence of two or more complications (P=0.247), life-threatening severe complications (P=0.0577), and stent obstruction by sludge (P=0.0912).

Conclusion: When compared with bilateral biliary drainage, unilateral biliary drainage is associated with a lower incidence of liver abscess as well as a comparable outcome of stent patency time and complication-free survival. We therefore propose that hilar biliary obstruction can be treated first by unilateral drainage with a metallic stent and by bilateral drainage only in patients who develop cholangitis in the contralateral biliary tree.